Britain and Sweden agreed on Friday to study air combat co-operation over the next decade and opened the door to other potential partners in a move that could see the Scandinavian country join a planned next-generation UK fighter project. Britain last year unveiled plans for a fighter plane and cohort of drones named Tempest, raising questions about the future of European defense co-operation as France and Germany pursue their own air combat program to meet growing threats. Tempest, meant to eventually replace the Eurofighter Typhoon from 2040, will be developed and built by BAE Systems, Britain's biggest defense company, alongside UK engine maker Rolls-Royce, the UK arm of Italian defense firm Leonardo and European missile maker MBDA. Sweden's Saab will not immediately join the same industrial team, but will be involved in a broader technology study that sketches out Britain's post-Brexit defense partnerships and could lead to further countries coming on board, officials said. "Brexit or not, Sweden has a strategic interest to further deepen its relations with the UK," Swedish Defense Minister Peter Hultqvist said at the Royal International Air Tattoo, a major military air show held in western England. Britain's defense ministry said the agreement called for a joint combat air development and acquisition program. However, Sweden said the plan allowed both sides to carry out studies with other partners and stressed its Gripen fighter would meet its air power needs "for the foreseeable future". Industry analysts say Sweden is at pains to ensure it is taken seriously as a standalone developer of Saab's Gripen fighter in any future tie-up rather than as a junior supplier. The study, which is expected to yield an initial report by autumn 2020, "lays the foundations for collaboration and invites others to participate in our discussions," Britain's Defence Procurement Minister Stuart Andrew said. Britain will remain a key partner for its European neighbors in NATO after leaving the European Union, he said. Britain and Sweden have conducted joint exercises in the Baltic where Western officials say Russia has stepped up probing flights and mock bomb runs near Europe's borders since 2013. European nations face a combination of security threats and budget constraints that have spurred competing alliances as the region's fragmented defense industry vies for leadership and a slice of future spending on any new pan-European fighter. Analysts say it is unclear whether Europe can afford more than one fighter program in future rather than the current three — the French Rafale, Swedish Gripen and multinational Eurofighter, which includes Britain. But defense analyst Francis Tusa said the amount of detailed work already undertaken by Britain and Sweden in the past year suggested the Tempest and Franco-German Future Combat Air System would both go ahead as separate projects. Differences in the way Britain and France handle aircraft carrier operations and their nuclear roles have historically made it hard for them to unite around a single aircraft project and this is likely to remain a big hurdle in future, Tusa said. — Reuters